The following graph shows a complete history of one year’s worth of daily sales records.

The associated Australian overall paid apps ranking is as follows:

So there have been a number of peaks and troughs. The single biggest factor causing those peaks and troughs appears to have been Apple promotions in the Hot / New / Staff Pick lists. But this has worked both ways – the biggest troughs have occurred when Apple has promoted competing apps.

The second biggest factor has been the weather itself. In Australia it seems that people are more interested in summer weather than they are in winter weather, hence causing an underlying annual cycle which peaks in summer (Dec/Jan/Feb) and troughs in winter (Jun/Jul/Aug).

Some individual weather events (eg. extreme heat waves, major rainfall events) seem to account for much shorter term peaks – especially noticeable around Feb 2009 when a major app update was also released.

Its also worth noting that during the course of the year the number of competitors has grown substantially. No doubt other developers have noticed how well weather apps seem to do in the app store ecosystem, and I would guess that my blogging about such attractive sales figures has probably encouraged some of the new ones into the game too. 😉 However, most of the newer competitors have failed to get any significant visibility, at least so far, and overall I don’t regret my decision to be transparent and open with my sales figures. I am always delighted to read about the inside stories of other app developers’ successes and failures, and hope that my own story has been interesting and useful to others too.